I just did this one through this morning. I paused at each insert card between the power circuits and drills to let my HR down a little (there are not sufficient recoveries between circuits and drills). It took me 86 mins to get through the whole thing, but it was worth it! It was awesome! With lots of variety, you won't get bored despite the long length. It felt like the Body Max of cardio. It will definitely burn TONS of calories (I burned 706 today) and help out your cardiovascular endurance. I really liked it a lot! Due to the length, I won't be doing it super often, but it's great when you're really ready for a cardio challenge! The drills weren't so bad after the power circuits, 'cause they're not step and very different feeling. I also had no freezing issues, but I haven't with any of the DVDs, either. HTH!
Carol